FIELD OF THE INVENTION
The present invention generally relates to a double conveyor gallery structure
with small span used in coal handling plant of a thermal power plant. More
particularly, the present invention relates to a weight optimized and short-
spanned double conveyor gallery system for coal handling plant.
BACKGROUND OF THE INVENTION
The double conveyor gallery is one of the important systems in coal handling
plant. The double conveyor gallery allows transportation of the material from
port or storage yard to bunker and then to the boiler. The storage yard is
normally located far away from the thermal power station for safety purpose. So,
the coal needs transportation for a long distance along conveyor galleries. These
galleries can be of various lengths supported by the trestle devices and transfer
towers where a conveyor has to change its direction. In general, a double
conveyor gallery comprises two conveyors belts and its supporting
arrangements, space for walkways, provision for fire fighting pipes including
potable water pipes, cable trays, lighting arrangements. The gallery is covered by
roof sheets and side sheets to protect the coal from any transmission loss due to
wind or rain.
The present invention is regarding the complete design optimization of one such
standard double conveyor gallery. The present invention of double conveyor
gallery structure per se constitutes two end portal frames, plurality of
intermediate portal frames, walkway beams, lattice girders, purlins, side runners,
rafters and bracings. The present invention bridges the gap of optimized design
from conventional design for a double conveyor gallery.

The prior art documents CN202080735U and CN202080669U discloses a system
having a portal-rigid frame substructure positioned inside a truss main structure.
However, the system configurations are different from each patent. The main
object of these prior art is to prevent the system from fire hazards and corrosion
effects rather than focusing on optimizing the structural member including
joining process so as to produce a system with reduced weight.
The existing designs for double conveyor galleries consist of only standard rolled
sections (flat members) and include a large number of built-up and heavy
sections. Under utilization of material in the prior art systems increases total
weight of the structure. Further, presence of built-up sections in the design
increase welding requirements which in turn enhances the fabrication time ad
cost. Thus, the prior art fails to address the problems of optimizing the system to
ensure maximum utilization of material, reduction in welding requirement,
minimizing the number of built up sections, and reducing the overall weight of
the system.
OBJECTS OF THE INVENTION
It is therefore an object of the present invention to propose a weight optimized
and short-spanned double conveyor gallery system for coal handling plant, which
eliminates the disadvantages of prior art.
Another object of the invention is to propose a weight optimized and short-
spanned double conveyor gallery system for coal handling plant, which utilizes
structural members including a joining sequence determined through technical
analysis.

A still another object of the invention is to propose a weight optimized and short-
spanned double conveyor gallery system for coal handling plant, which can
withstand heavy wind load conditions.
A further object of the present invention is to propose a weight optimized and
short-spanned double conveyor gallery system for coal handling plant, which is
operable at various heights from the ground.
A still further object of the present invention is to propose a weight optimized
and short-spanned double conveyor gallery system for coal handling plant, which
prevents excessive deflection of the system by delimiting developed stresses to
safe limits under severe wind load conditions.
SUMMARY OF THE INVENTION
According to the invention, pipe sections are introduced in the conveyor galleries.
Almost 20% of the structural components of the gallery are made of pipe
sections. Pipe sections are preferred over standard flat sections because of the
following reasons,
i. The force coefficient of circular sections are almost 30% less when
compared to flat sections which results in huge reduction in wind load
acting on the structure,
ii. The load carrying capacity increases because of increase in moment of
inertia.
iii. Circular section may have as much as 30 to 40% less surface area
than that of an equivalent rolled shape and thus reduces the cost of

maintenance, cost of painting.
iv. There is no better section than the tubular one for torsional resistance.
v. Tubes are of special interest to architect from an aesthetics view point.
Accordingly there is provided a weight optimized and short-spanned double
conveyor gallery system for coal handling plant the system comprising two end
portal frames one each located at a first and a second end of the conveyor
gallery system, and a plurality of intermediate portal frames each interposed
between the first and second end at equi-distance spacing.
These end portal frames are formed of a plurality of vertical side members,
multiple horizontal beams at the top and bottom, and multiple inclined roof
members and stiffeners. Similarly the intermediate frames consist of a plurality of
vertical side member, multiple horizontal beams at the top and bottom, multiple
inclined roof members (rafters), and a plurality of truss members at top and
bottom. The end portal frames and the intermediate frames are connected by
bottom chord members for example, walkway beams, lattice girders and bracings
at the bottom; and top chord members for example, lattice girders and bracings
at the top, side runners at the sides, purlins at the top of the inclined members.
According to the present invention, technical parameters for the proposed
system are input and processed in a computer apparatus to generate a
mathematical model which inter alia is used to further process the data by
applying the load acting data on the system. Accordingly, the constituent
members including a forming process is developed such that overall weight of
the system is reduced, and code provisions including stability of the structure is
maintained. The system is then used for fabrication of the structure.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
The accompanied drawings described the invention in detail and illustrate the
features; aspects, and advantages of the present invention. Reference numerals
are used for locating the component of the system. The invention may be readily
understood and carried into practical effect based on the following description
taken the conjunction with the accompanying drawings, wherein:
Figure 1 - shows a side view of the double conveyor gallery system of the
invention
Figure 2 - shows a front view of the double conveyor gallery system of the
invention
Figure 3 - shows an expanded view of an end portal frame (A) of the
conveyor gallery system of figure 1.
Figure 4 - shows an expanded view of an intermediate portal frame (B) of the
conveyor gallery system of figure 1.
Figure 5 - shows an enlarged view of a bottom chord member (C) of the
system of figure 1.
Figure 6 - shows an enlarged view of a top chord member (D) of the system
of figure 1.
Figure 7 - shows a magnified view of side members (E) of the system and
marked in figure 2.

Figure 8 - shows a magnified view of roof top members (F) of the system as
marked in figure 2.
DETAILED DESCRIPTION OF THE INVENTION
Figure 1 shows the side view of the double conveyor gallery in accordance with a
preferred embodiment of the invention, Two end portal frames (A) which are
Placed at the beginning and at the end of the conveyor gallery structure are
connected by a plurality of intermediate frames (B). At the bottom, as shown in
figure 2, a plurality of bottom chord members (C) connects both the end portals
frames (A) and the intermediate portals frames (B) in a longitudinal direction. At
the top, the top chord members (D) connect both the end portal frames (A) and
the intermediate portals frames (B) in the longitudinal direction. At the sides the
side bracing along with side runners (E) (see figure 7) connects the frames on
both sides. At the roof top (F), the purlins are shown in figure 8.
According to the invention, the portal frames (A) as shown in figure 3 consists of
a horizontal bottom beam (1) connected to the side vertical of the end portals
(2a and 2b) which is associated with the inclined roof members (3a and 3b) The
horizontal top beam (5), inclined stiffeners at top and bottom (4a, 4b 4c 4d)
horizontal stiffeners (4e) and vertical stiffeners (23) are provided for additional
stability along with the other members. At the bottom of the side verticals (2a
and 2b) of end portals, the supporting members (6a and 6b) are connected. The
end portal frame (A) is made up of standard I sections.
The intermediate portal frames (B) (see figure 4) are placed at an equi-distance
in between both the end portal frames (A). It consist of a plurality of horizontal
bottom member (7) fastened to the intermediate side vertical (8) and at the top
with rafter connections (9a and 9b) and horizontal top member (11). The rafter

connections (9a and 9b) and the horizontal top member (11) are linked with a
plurality of truss members (10a, 10b, 10c, lOd, lOe, lOf, lOg, lOh, lOi, lOj, 10k
111, 10m). Both rafters and the truss members are made up of pipe sections.
The side verticals (8), horizontal top members (11) and horizontal bottom
members (7a), are all made up of standard channel sections. Built-up sections
made with parent section are used at the high stress regions of the horizontal
bottom members (7b). The inclined truss members (12a, 12b, 12c, I2d, I2e, I2f,
12g, 12h, 12i, 12j) and horizontal cross beams (13) provided at the bottom of
each intermediate portal (all are made up of pipe sections), ensures additional
stiffness to the horizontal bottom member.
The bottom chord member (C) (see figure 5) consists of a plurality of connecting
members attaching the bottom part of the frames. It consists of lattice girder
(14a, 14b) on both sides. In between, the walkway beams (15a, 15b, 15c, and
15d) are provided to support the walkway floors and the conveyor belt supports.
These are again standard channel sections but of lower size than the lattice
girder. Horizontal cross beams (13) and lattice girders (14a, 14b) are interlinked
by bottom bracings (16) made up of pipe sections. The top chord member (D)
consists of a plurality of connecting members attaching the top plane of the
frames. The lattice girder (17a, 17b) consists of box sections made up of
standard channel sections. The lattice girders and the horizontal top members
(11) at the top chord are inter-connected by bracings (18) made up of pipe
sections.
At the sides (E) (see figure 7) the side bracings (19a and 19b) are used to
connect the end portals and the intermediate portal frames. They are made up of
standard pipe sections. The side runners (20a, 20b, 20c, 20d, 20e, 20f) hold the
side sheeting and are supported by the portal frames in the longitudinal
direction. These side runners are made up of standard channel sections.

At the roof top (F) (see figure 8) the purlins (21a, 21b, 21c, 21d, 21e, 21f, 21g,
21h, 21i and 21j) are connected along the longitudinal direction. The purlins are
used to hold the roof sheeting and are supported at the inclined roof level at
certain intervals. Walkway runners (24a to 24f) are provided at the bottom chord
in order to support chequered and seal plates, these members are made up of
standard channel sections.
In order to account for the high stress levels, side bracings (19a, 19b), and
rafters (9a, 9b) employed at the end of gallery span are provided with heavier
sections than those at the intermediate locations.
For example, a double conveyor gallery at the range of 10 to 14m span can be
taken to explain the process of this proposed system. The structural data
considered are as follows



The logic generated takes into account the above parameters and place the
frames at the respective locations and connect accordingly. The members are
grouped according to their function and location and the logic to select the
properly is given in such a way that each group has a particular section size.

The following table gives the comparison between the prior art and the inventive
system formed with pipe sections, for a given set of aforementioned parameters.



From the above table it is seen that structural arrangement with pipe section,
local stiffening arrangement and bracing pattern, the above said structural
arrangement has lower structure weight and reduced number of built-up sections
which reduces the welding requirements. These make the present invention to
be better than the existing structural arrangement.
The inventive system can be used for any material handling plant like coal, steel,
lime etc., because the model developed provide data irrespective of the material
being carried.
While the illustrative embodiments of the disclosure has been described above, it
will be recognized and understood that various modifications can be made to the
embodiments and the appended claims are intended to cover all such
modifications which may fall within the spirit and the scope of the disclosure.

WE CLAIM
1. A weight optimized short-spanned double conveyor gallery system for coal
handling plant, comprising:
- at least two end portal frames disposed at each end of the system;
- a plurality of intermediate portal frames placed at an equi-distance in
between both the end portal frames ;
- a plurality of bottom chord members connecting the intermediate
portal frames and the end portal frames in a longitudinal direction at
the bottom portion of the system;
- a plurality of top chord members connecting the end portal frames and
the intermediate portal frames at the top portion of the system;
- a plurality of rooftop members connecting along the longitudinal
direction; and
- a plurality of side runners connecting the system at both sides,
2. The system as claimed in claim 1, wherein the end portal frames are
made of a plurality of frames, each frame enclosing a roof portion, and a
plurality of side vertical members extending downwards from the roof
portion, the side vertical members having and a plurality of side stiffeners,
and horizontal bottom and top members with vertical stiffeners disposed
in-between, leaving an opening in the middle of the end portal frames.

3. The system as claimed in claim 1, wherein the intermediate portal frames
consist of a plurality of frames, each frame enclosing a roof portion, and
plurality of side vertical members extending downwards from the roof
portion, and a plurality of truss members and horizontal top members,
leaving an opening in the middle of the intermediate portal frames.
4. The system as claimed in claim 1, wherein the bottom chord members
comprising a plurality of lattice girders connecting the ends of the end
portal frames and intermediate portal frames along with walkway beams
and walkway runners in between in the longitudinal direction along with
proper bracing pattern in order to form a support device at the bottom
plane, and wherein a plurality of truss members connected below the
horizontal members to horizontal cross-beam in order to enhance the
strength of the bottom chord.
5. The system as claimed in claim 1, wherein the top chord members
comprising a plurality of lattice girders connecting the ends of the end
portal frame in the longitudinal direction with a bracing pattern in order to
form a support device at the top plane.
6. The system as claimed in claim 1, wherein the roof top members
comprising a plurality of purlins connecting the end portal frames and
intermediate portal frames in the longitudinal direction with bracing at the
top plane of the roof in order to support the roof sheeting.
7. The system as claimed in claim 1, wherein side runners, in order to
support the side sheeting, connected to the end portal frames and
intermediate portal frames in the longitudinal direction with the proper a
bracing pattern at the side planes.

8. The system as claimed in claim 1 or 2, wherein the side verticals consist of
standard I sections.
9. The system as claimed in claim 1 or 3 2, wherein the horizontal bottom
members are made up of standard I sections.
10. The system as claimed in claim 1 or 2, wherein the inclined roof portion
consists of standard I section connected with side stiffener which is made
up of standard I section cut beam.
11. The system as claimed in claim 1 or 2, wherein the horizontal top
members are made up of standard channel section connected to side
verticals for higher stability.
12. The system as claimed in claim 1 or 2, wherein the vertical member made
up of standard angle section and connected between the horizontal top
member and the inclined roof portion.
13. The system as claimed in claim 1 or 3, wherein the horizontal bottom
members consist of plurality of standard channel sections except at
specified high stress regions and such locations are made up of built-up
channel sections.
14. The system as claimed in claim 1 or 3, wherein the bottom truss members
and horizontal cross beams are made up of pipe sections.
15. The system as claimed in claim 1 or 3, wherein the side verticals are made
up of a plurality of standard channel sections.

16. The system as claimed in claim 1 or 3, wherein the roof portion consists of
pipe sections connected by tubular truss members.
17. The system as claimed in claim 1 or 3, wherein the horizontal top beam is
made up of standard channel sections connected to the side verticals.
18. The system as claimed in claim 1 or 4, wherein the lattice girder consists
of built-up channel section connecting the frames in the longitudinal
direction.
19. The system as claimed in claim 1 or 4, wherein the walkway beam is
made up of standard channel section.
20. The system as claimed in claim 1 or 4, wherein the walkway runners are
made up of standard channel section.
21. The system as claimed in claim 1 or 4, wherein the intermediate portal
frames and end portal frames are connected by bracings made of pipe
section.
22. The system as claimed in claim 1 or 5, wherein the lattice girder
connecting the intermediate portal frames and end portal frames are box
section made up of standard channel section.
23. The system as claimed in claim 1 or 5, wherein the intermediate portal
frames and end portal frames are connected by bracings made of pipe
section.

24. The system as claimed in claim 1 or 6, wherein the purlins are connected
on top of the roof members in order to support the roof sheeting and
constitute standard channel sections.

ABSTRACT

The invention relates to a weight optimized short-spanned double conveyor
gallery system for coal handling plant, comprising at least two end portal frames
disposed at each end of the system; a plurality of intermediate portal frames
placed at an equi-distance between both the end portal frames; a plurality of
bottom chord members connecting the intermediate portal frames and the end
portals frames in a longitudinal direction at the bottom of the system; a plurality
of top chord members connecting the end portal frames and the intermediate
portal frames at the top portion of the system; a plurality of roof top members
connected along the longitudinal direction; and a plurality of side runners
connecting the system at both sides. Intermediate portal frames consist of
plurality of localized stress regions which are strengthened with built-up sections
made from the parent section. Plurality of members in the side bracings and
rafters employed at the end of gallery span are provided with heavier sections
than those at the intermediate locations.